Strip-edge folder



Nov. 22, 1927. 1,650,198

J. DERRY STRIP EDGE FOLDER Filed Oct. 20. -1sa24 3 Sheets-Sheet 1 Nov. 22, 1927.

J. DERRY STRIP EDGE FOLDER Fi1ed 0ct.20. 1924 3 Sheets-Sheet 2 W FNT R by RWQQQM IQ ATTEFKPIEY- Nov. 22, 1927.

J. DERRY STRIP EDGE FOLDER 4 2 9 1 0 2 t c o d e l 1 F INVENTU m a "ATT RN y Patented Nov. 22, 1927.

UNITED STATES PATENT OFFICE.

JASPER DERBY, F MEDFORD, MASSACHUSETTS, ASSIGNOR TO ANDREW TEBKELSEN, OF BOSTON, MASSACHUSETTS.

. STRIP-EDGE FOLDER.

Application filed October 20, 1924. Serial No. 744,863.

This invention relates to a device for folding the edge of a paper or similar flexible strip, and especially, although not exclusively, to the strip edge folding devices employed in machines for spirally wrapping annular objects, such as pneumatic tires and the like, with a strip of paper having its exposed edge folded under to reinforce the same.

The invention has for its object to provide a strip edge folding device of simple and unitary construction, which may, if desired, be in the form of an integral casting, said device having an unobstructed surface upon which the strip may be readily placed without threading, said surface being of such a character that when the strip is drawn longitudi nally thereover under tension its edge will, without preliminary folding and irrespective of the position initially assumed thereby, be

0 automatically turned and folded under the body of the strip for an even and predetermined width.

The foregoing and other objects of the invention, together with means whereby the latter may be carried into effect, will best be understood from the following description of one embodiment and application thereof illustrated in the accompanying drawings. It will be understood, however, that the particular construction described and shown has been chosen for illustrative purposes merely, and that the precise form of the invention, as defined by the claims hereto appended, is susceptible of considerable variation without departure from the spirit and scope thereof.

In said drawings:

Fig. 1 is a side elevation of a tire wrapping machine having a strip edge folder embodying the invention.

Fig. 2 is a plan view of the folder detached.

Fig. 3 is a View similar to Fig. 2 showmg the strip as initially applied to the folding device preliminary to the folding operation.

45 Fig. 4 is a side elevation of the parts shown in Fig. 3.

Figs. 5, 6 and 7 are transverse sections taken substantially on the lines 55, 6-6. and 7-7, Figs. 3 and 4.

" Figs. 8, 9, 10, and 11 are fragmentary views similar to Fig. 3, illustrating successive stages in the folding operation as the strip is moved longitudinally in the direction of the arrows from the position shown in Fig. 3.

Figs. 12, .13, 14, and 15 are fragmentary transverse sections taken substantially on the lI11 nes81212, 13-13, 14 -14, and 15-15,

Figs. 16, 17, 18 and 19 are similar sections on the llnes 1616, 17-17, 1818, and 19 19, Fig. 9.

Figs. 20, 21, 22, and 23 are similar sections on the lines 2020, 2121, 2222, and 23-23, Fig. 10.

Fig. 24 is a similar section on the line 24-24, Figs. 11 and 25.

Fig. 25 is a longitudinal section on the line 25 25, Fig. 11.

Figs. 26 and 27 are detail sections on the lines 2626 and 27-27, Figs. 11 and 25.

While the invention may be otherwise employed, it is shown in Fig. 1 as applied to a machine for spirally wrapping automobile tlres with a helically wound strip of paper. As shown, the frame of the wrapping machine comprises a bracket 20 adapted to be secured in projecting position to the edge of a bench or table (not shown) and including a yoke portion 21 having an open top and a circular series of rollers 22, 23, 24, 25 and 26 for rotatably supporting an annular shuttle 27 formed with an opening 28 adapted to register with the open top of the yoke in order to permit insertion of the tire. or other work W.

Said tire W is supported with its uppermost portion centered with respect to the shuttle 27 y means of a pair of work supporting rollers one of which is shown at 29, said rollers being carried by shafts 30, journalled in suitable hearings in the frame 20 and connected by worm gearing 31 with a shaft 32 also journalled in suitable hearings in the frame and carrying the shuttle supporting roller 25. The shuttle 27 and work supporting rollers 29 are, therefore, connected for simultaneous rotation in synchronism, the arrangement being such that the work W is turned relatively slowly with respect to the shuttle 27. The rollers 25 and 26 are engaged and rotated by a friction disk 33 rotatably supported on the frame and in turn engaged and rotated by a friction pinion 34 on the shaft of an electric motor 35 having a base 36 pivoted to the frame and adapted to be raised and lowered, to engage the pinion 34 with the disk 33 and disengage the same therefrom, by means of a manually operated lever 37.

The wrapping material, preferably in the form of a continuous strip S of paper, is supplied from a roll 38 rotatably supported on the yoke 27 and whose rotation is resisted, to apply tension to the strip, by means ofa friction brake 39. From the roll 38 the strip S passes to the tire W over the folding device, designated as a whole in Fig. 1 by the letter F, to which the present invention relates, and the preferred construction of which, as shown in the remaining figures of the drawings, will now be described.

The folding device F is preferably in the form of a unitary casting comprising a laterally projecting body portion 4 over wh ch the strip S is drawn and an angular guide flange 41 for the edge of the strip opposite that to be folded, said flange being formed with perforated bosses or lugs42 adaptedto receive bolts 43 (Fig. 1) by which the device is secured to the face of the shuttle 27 The body portion 4 of the folding device is formed with a longitudinally convex and preferably curved surface A to receive the strip S and adjacent its free edge, or the edge opposite the flange 41, is intercepted by a recess or notch 5. As shown, the notch 5'is diagonally disposed with respect to the length of the strip, its forward end 45 being open to the free edge of the body portion 4, and its rear end 46 intercepting the paper receiving surface of the device intermediate the edges of the latter. Laterally beyond the recess or notch 5, the body 4 is provided with a projection 6 which is preferably in the form of a horn or spur of greater height than the depth of the notch so as to extend above the surface A. The born or spur 6 defines the outer side 47 of the notch 5, which outer side, as shown, converges toward the middle of the strip in the direction of movement of the latter. The strip receiving surface A of the device adjacent the notch 5 is preferably slightly laterally, as well as longitudinally, convex, having a slightly raised portion 7 immediately adjacent said notch and from which the latter falls abruptly away to form a shoulder 8.

hen the wrapping operation is begun,

the strip S is placed flatwise upon the surface of the body 4 of the device with its edge a opposite the edge I) to be folded (Figs. 3, 4 and 5) in engagement with the flange 41. The end of the strip is then carried to the tire W (Fig. 1) and is held thereagainst by hand as the machine is started, causing the strip to be drawn from the roll 38 over the folding device under tension. The folder is preferably so designed with respect to the width of the strip to be used that the lateral spacing, or minimum lateral distance between the flange 41 and the born or spur 6 is less than the width of the strip by the width of the desired fold. When, therefore, the strip is placed on the device in the manner referred to, the edge I) will be turned outwardly or upwardly against the spur 6,

5 is straight, so that the distance along said line between its points of tangency f, g with the strip receiving surface A at the ends of the notch is shorter than the distance, meas ured along the corresponding or intervening portion of the surface A, at the inner side of the notch. It therefore follows that, due to the tension on the strip, the marginal portion h of the latter immediately adjacent the portion 0 tends to be drawn down into the notch as shown particularly in Figs. 4 and 5, this tendency being increased by the raised or laterally convex portion 7 of the surface. As tension is initially applied to the strip it is found that the forward end of the shoulder 8 tends to form in the strip a longitudinal crease 2' (Figs. 3, 5, and 7), and that there is also a tendency to form a second longitudinal crease k at the bottom of the notch 5, the latter crease, due to the fact that the marginal portion of the strip is, to a certain extent, drawn about the born 6, converging forwardly toward the edge I) of the strip, the crease i at its rear end meeting the crease 7c and at its forward end merging into a curve or roll 7'. A double fold is thus formed in the marginal portion h of the strip, said fold comprising a downwardly turned portion Z between the creases i and k and an upturned portion m between the crease k and the edge I). As the strip is moved rearwardl or in the direction of the arrows, the portion m is crowded against the outer side of the notch 5 formed by the horn 6, and is therefore forced inwardly under the portion Z, as indicated in Figs. 8 and 13, and the portion I forced inwardly under the body of the strip. This relieves ins the tendency of the material to be creased along the line i by the shoulder 8, so that said material thereafter rolls smoothly over the forward end of said shoulder, as indicated at j (Fig. 15), while said shoulder, due to its inclined or diagonal position in the construction shown, recedes from the crease 2', as shown in Figs. 13, 17 and 18, as the strip moves rearwardly, said crease being eventually flattened down by engagement with the portion 48 of the surface A at-the rear and outer side of the notch or recess 5, as shown in Figs. 12 and 16-. By reasonof the convergence of the crease k with the edge I) of the strip as shown in Figs. 3 and 8, the width of the upturned portion m diminishes as the strip moves rearwardly, as will be seen by comparison of Figs. 5, 6, and 7, Figs. 12, 13, 14, and 15, Figs. 16, 17, and 18. and Figs. 20 and 21, the end of said portion m passing the horn 6 substantially concurrently with the end of the crease 2', thus disposing of that portion of the margin of the strip which, due to its mode of applica- 'llu tion to the folder, was initially upturned, as

, above explained. Thereafter the marginal edge portion of thestrip, designated by the letter 0 in Figs. 11, 19, 22, 23, 24, 26, and 27, is drawn into the recess 5 by the tension on the strip, as above explained, being turned or rolled entirely under, as shown at j, for a constant width. Engagement of the roll or loose fold j with the horn 6, or outer side 47 of the recess '5, as-shown at n in Fig. 24, tends to crease the material lightly along this line, said crease a being tightened, and the folded under portion 0 flattened down, by the subsequent passage thereof over the portion 48 of the folder, as shown in Figs. 11, 25, 26, and 27.

From the foregoing it will be seen that no particular care is necessary in placing the strip upon the folding surface, and that, notwithstanding the fact that when a new strip is placed thereon the edge 1) tends to be turned outwardly by the horn or spur 6, said edge will nevertheless, as the strip is moved longitudinally under tension, be turned under and a tight fold of constant width formed as the strip passes over the folder. It therefore follows that the folder is extremely convenient to use and results in the saving of considerable time heretofore required in the use of similar devices in initially folding the strip or in threading the same through the complicated. passages necessary in order to insure the accurate folding thereof. It will also be seen that the device involves no complicated or relatively moving parts and can therefore be constructed as an integral casting at slight expense.

In order that the invention may be clearly understood, certain operations incidental to the folding of a relatively stiff paper strip by means of the specific device shown have been above described with considerable particularity, but the exact nature of these operations is susceptible of considerable variation depending upon the precise construction employed, and even of some variation in the use of the same construction with different materials or in handling the materials in dif ferent ways in the starting of the folding operation, the ultimate result, namely, that of turning under and folding a marginal edge portion of a strip for a constant width, being, however, the same in all cases. As

' will be seen, the essential elements of the invention, broadly considered, comprise only a longitudinally convex surface over which the strip to be folded is drawn under tension, a recess at one side of said surface providing a path for the marginal edge portion of the strip of less length than the length of the corresponding portion of the surface, and into which said edge portion of the strip tends to become depressed by the tension on the latter, said recess being defined at its outer side by a projection or wall which engages the mar inal portion of the strip, crowding it si ewise and causing it to be turned into said recess under the body of the strip irrespective of its initial position when recess at an inclination to the path of the.

strip, the operation of the device is facilitated and the desired results more positively insured. Also, by providing a portion or surface beyond the recess over which the folded marginal portion is drawn, the fold is flattened and the crease ti htened. More over, by providing a projection in the form of a born or spur which extends above the strip receiving portion of the device, the application of the strip is facilitated and danger of accidental tearing eliminated. Furthermore, by providing a guide for the edge of the strip opposite that to be folded, and by spacing said guide from the projection a distance less than the width of the strip by the width of the desired fold, a fold of even width is insured.

.The rear edge 51 of the body of the folder is preferably formed at an inclination corresponding to that at which the strip is led from the shuttle to the work, this inclination depending upon the relative speed of movement of the shuttle and work and the consequent pitch at which the strip is wrapped. No additional guiding device for the strip is therefore necessary, since the device described operates to lead the strip from'the shuttle to the work at the proper angle as well as to fold the edge thereof.

Having thus described my invention, I claim:

1. A folder comprising a longitudinally convex supporting surface over which the strip is fed, said surface having at one side a recess transversely closed at the rear end thereof and into which the edge of the strip is turned under the body of the strip, and means for causing the strip to travel over said surface in a predetermined path.

2. A strip folding device comprising a body having a supporting surface unob structed to permit the strip to be .freely placed thereon and having an abutment at one side for positioning an edge of the strip, said body also having means at the opposite side capable of forming in the opposite free edge of the strip during the feeding of the strip a uniform fold irrespective of the initial position of said free edge prior to feeding the strip.

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3. A folding device comprising a body having a surface upon which the strip may be freely placed fiatwise and over which the strip is fed, said body having guiding and folding means capable of forming a uniform edge fold in the strip in any position in which the strip is initially placed on said surface.

4. A strip edge folder having a longitudinally convex surface over which the strip is drawn, said surface having at one side a recess through which a marginal portion of the strip passes along a line of less length than the length of the corresponding portion of said convex surface, and a projection at the outer side of said recess for engaging the adjacent portion of the strip, said surface having a continuation thereof beyond said recess longitudinally of the strip, over which said marginal portion is drawn after leaving said recess.

5. A strip folder comprising a longitudinally convex supporting surface over which the strip is fed, said surface having at one side a lengthwise extending groove open at its forward endand intercepted rearwardly of said open end by a transversely extending wall portion adapted to turn under the edge of the strip, and means for causing the strip to travel over said surface in a predetermined path.

6. A strip edge folder having an unobstructed longitudinally convex surface upon which the strip may be freely placed fiatwise and over which it is drawn, arecess at one side of said surface through which a marginal portion of the strip PRSTGS along a line of less length than the length of the corresponding portion of said surface, and a projection at the outer side of said recess for engaging the adjacent portion of the strip.

7. A strip folder comprising a longitudinally convex supporting surface over which the strip is fed, said surface having at one side a lengthwise extending groove open at its forward end and closed at its rear end and into which the edge of the strip is turned under the body of the strip, and means for causing the strip to travel over said surface in a predetermined path.

8. A strip edge folder having a longitudinally convex surface over which the strip is drawn, said surface being intercepted adj acent one edge by a notch Whose outer side is disposed diagonally with respect to the length of the strip, and means for causing the strip to travel over said surface in a predetermined path.

9. The combination with means for longitudinally feeding a flexible strip under tension, of a folder having a longitudinally convex surface over which the strip is drawn and a notch adjacent one edge, the outer side of said notch converging toward the middle of said strip in the direction of movement of the latter, and means for causing the strip to travel over said surface in a predetermined path.

10. A strip edge folder having an unobstructed surface upon which the strip may be freely placed fiatwise and over which it is drawn, said surface being longitudinally convex and being intercepted adjacent one edge by a diagonally disposed notch, and means for causing the strip to travel over said surface in a predetermined path.

11. A strip edge folder having a longitudinally and transversely convex surface over which the strip is drawn, said surface being intercepted adjacent one edge by a notch whose outer side is disposed diagonally with respect to the strip, and means for causing the strip to travel over said surface in a predetermined path.

'12. A strip edge folder having a longitudinally convex surface over which the strip is drawn, said surface bein intercepted adjacent one edge by a note whose outer side is disposed diagonally with respect to the length of the strip, and said surface having a raised portion adjacent the inner side of said notch.

13. A strip edge folder having a longitudinally convex surface over which the strip is drawn, said surface being intercepted adjacent one edge by a diagonally disposed notch, and a horn forming the outer side of said notch and extending above said surface.

14. A strip edge folder having an unobstructed surface upon which the strip may be freely placed fiatwise and over which it is drawn, said surface being longitudinally convex and being intercepted adjacent one edge by a diagonally disposed notch, and a horn forming the outer side of said notch and extending above said surface.

15. A strip edge folder having a longitudinally convex surface over which the strip is drawn and a diagonally disposed notch open at its forward end to the edge of said convex surface and at its rear end intercepting the latter at a point between its edges, and means for causing the strip to tI3,\1'6l over said surface in a predetermined at i.

p 16. The combination with means for longitudinally feeding a flexible strip under tension along a predetermined path, of a folder having a longitudinally convex surface over which the strip is drawn, a diagonally disposed notch adjacent one edge, and an inclined end over which the strip passes in leaving the folder, and means for causing the strip to travel over saidsurface in a predetermined path.

In testimony whereof I afiix my signature.

JASPER DERRY.

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